Phase I, multi-center, randomized, double-blind study. Group B Streptococcus type III - tetanus toxoid conjugate vaccine will be administered to healthy, non-pregnant adult volunteers. A single dose of one of three vaccine concentrations with or without alum will be given intramuscularly. Subjects will be randomized to one of four groups. Backround: Group B Streptococcus (GBS, Streptococcus agalactiae) has been recognized as a major cause of neonatal sepsis and meningitis in the United States for more than 25 years. It is also a significant cause of pregnancy-related morbidity (i.e. bacteremia, chorioamnionitis, urinary tract infection) affecting at least 50,000 women annually in the United States. There has been increased recognition during the past decade that GBS infections are a major public health problem in nonpregnant adults. It has been estimated that in the U.S. about 8,000 cases of GBS disease occur annually among persons 15 years of age and older. Risk factors that hae been identified for GBS disease in nonpregnant adults include age <60 years, chronic illnesses such as diabetes mellitus, cirrhosis, renal failure, neurologic disease, and immunosuppression from cancer or human immunodeficiency virus infection. The spectrum of clinical disease from GBS in adults includes primary bacteremia, skin and soft tissue infections, osteomyelitis, urosepsis, pneumonia, meningitis and endocarditis. Approximately 20% of cases of adult GBS disease are fatal. A strategy to prevent GBS disease through active immunization would potentially be of benefit not only for pregnant women and their newborns, but also for nonpregnant adults with defined risk factors. Purpose: 1) To asses the safety of a single injection of monovalent type III GBS polysaccharide-tetanus toxoid conjugate vaccines at different dosages with or without alum in healthy nonpregnant adults. 2) To determine the effect of an adjuvant, alum, on the immunogenicity of monovalent GBS type III polysaccharide-tetanus toxoid conjugate vaccines.